Usually furniture buy identical pairs. For example, two sliding chairs, beds. Over time, they grow obsolete, become an anachronism. Throw them away, but to alter… such chairs, released the same factory overall and mounting dimensions are the same. Because of this, after the dismantling of the side panel (legs) on each product it is possible to join the chairs into a sofa, and even his diagram of the folding-unfolding is unchanged.
Sequence alterations following. Remove the back pillows and sides, leaving intact the extreme. There is an opportunity to connect the base of the chairs together the holes of the mounting taken sides, using the same bolts. In such a modular structure of transverse bars work is composed of two halves. Therefore, in those places where dismantled supports (legs or joints), need reinforcement bars to ensure strength and rigidity of the frames.